"The Real World: Chicago" and frequent "Challenge" participant
Tonya Cooley has filed a lawsuit accusing her former
"Challenge: The Ruins" castmates
Kenneth Santucci and
Evan Starkman of violating her genitals with a toothbrush while MTV turned a blind eye to the sexual abuse.

According to TMZ, Cooley's lawsuit claims that while she was passed out -- and MTV was filming -- Santucci and Starkman "took another male participant's toothbrush and rubbed the toothbrush around plaintiff's genitals, including rubbing her labia and inserting the toothbrush into plaintiff's vagina."

Cooley then alleges producers replaced the toothbrush and didn't tell her what happened. She also says producers encouraged male cast members to "inappropriately touch female cast members' bodies, including in intimate areas," while stripped of their bathing suits. Apparently she and other female "Challenge" participants reported the incidents, but MTV didn't do anything about it.

Neither MTV nor Bunim/Murray, the company that produces "The Real World" and the "Challenge" shows, could be reached for comment.